An encrypted file system (EFS) is a secure file system that allows a user to securely store data utilizing symmetric and asymmetric cryptography. Encrypted file systems are typically supported on a single machine, and in order for a user to access the encrypted file systems, the user logs onto the same machine that stores the encrypted file systems.
A network file system (NFS) is a distributed file system that allows users to export data from one machine (server) and import/mount it from other machines (clients). Although network file systems may require passwords for a user to access particular file systems, the file systems themselves are typically unencrypted.